Innovation of the Year Award 2025: KEF’s VECO technology transforms bass performance

A pillar of four wires coiled very tightly. Each of them have a gold frame around them to form the VECO technology.
(Image credit: KEF)

If you have been following the coverage of the What Hi-Fi? Awards 2025, you will probably have spotted that the KEF XIO has taken home the crown for the Best Soundbar Over £1000 category.

For those who are yet to read our review, let us fill you in. The premium 5.1.2 ’bar blew us away during testing with its ability to create an immersive surround-sound experience, as well as its agile bass performance.

But there was something else that caught our attention in KEF’s design, and that has ultimately earned the company our Innovation of the Year Award.

Enter KEF’s Velocity Control Technology, or VECO for short, which the company says delivers “deep, best-in-class bass” performance. It aims to reduce distortion and increase accuracy with lower frequencies as much as possible.

How does VECO work?

KEF XIO soundbar

(Image credit: What Hi-Fi?)

VECO is, put simply, a form of motional feedback. This idea is far from new, with the first versions of this technology emerging as early as the 1970s. The clever thing here is how the company’s engineers have managed to integrate it into the soundbar’s quartet of P185 bass drivers.

Apologies, as we’re going to get geeky here. The drive unit’s traditional voice-coil former (the cylindrical component that the voice coil is wrapped around) is replaced with a flexible PCB onto which a carefully shaped sensing coil is embedded. This sensor allows the speed of diaphragm movement to be measured.

The clever processor inside the XIO knows what the input signal to the bass unit is, and now that it also knows the speed of movement of the diaphragm, it can identify any distortion in the driver’s output and compensate accordingly, in real time. And that’s not all that is incredibly impressive about KEF’s invention. The sensor and the drive unit’s electromagnetic circuits work separately without influencing each other.

All of this results in a deep and clean bass performance that is among the best we have heard in the premium soundbar category.

When we compare the XIO with the previous Award-winner – the Sennheiser Ambeo Soundbar Max – we find: “The KEF counters with more clarity, greater precision in the way sounds are rendered and notably more finesse in the way low-level dynamics are delivered.”

We continue: “It’s the more transparent performer, and it ultimately gives us greater insight into the soundtrack being played.”

This is KEF’s first implementation of the VECO technology, so we are especially interested to see what this development could mean for its products later down the line. Bring on the bass!

MORE:

Here's our review of the KEF XIO

What Hi-Fi? Awards 2025 winners revealed!

These are the best soundbars right now

Robyn Quick

Robyn Quick is a Staff Writer for What Hi Fi?. After graduating from Cardiff University with a postgraduate degree in magazine journalism, they have worked for a variety of film and culture publications. In their spare time, Robyn can be found playing board games too competitively, going on cinema trips and learning muay thai.

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